CVE-2021-1501— Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software SIP Denial of Service Vulnerability
Quick assessment
Affected
Cisco Cisco Adaptive Security Appliance (ASA) Software
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Cisco Firepower Threat Defense（FTD）是美国思科（Cisco）公司的一套提供下一代防火墙服务的统一软件。 Cisco Firepower Threat Defense 存在代码问题漏洞，攻击者可利用该漏洞导致受影响的设备崩溃和重新加载，从而导致DoS状态。
Possible ATT&CK Techniques 1 AI
T1499 · Endpoint Denial of Service
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I. Basic Information for CVE-2021-1501
Vulnerability Information
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Vulnerability Title
Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software SIP Denial of Service Vulnerability
Source: CVE Program / CVE List V5
Vulnerability Description
A vulnerability in the SIP inspection engine of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a crash and reload of an affected device, resulting in a denial of service (DoS) condition.The vulnerability is due to a crash that occurs during a hash lookup for a SIP pinhole connection. An attacker could exploit this vulnerability by sending crafted SIP traffic through an affected device. A successful exploit could allow the attacker to cause a crash and reload of the affected device.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
不充分的会话过期机制
Source: CVE Program / CVE List V5
Vulnerability Title
Cisco Firepower Threat Defense 代码问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Cisco Firepower Threat Defense（FTD）是美国思科（Cisco）公司的一套提供下一代防火墙服务的统一软件。 Cisco Firepower Threat Defense 存在代码问题漏洞，攻击者可利用该漏洞导致受影响的设备崩溃和重新加载，从而导致DoS状态。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| Cisco | Cisco Adaptive Security Appliance (ASA) Software | n/a | - |
|
II. Public POCs for CVE-2021-1501
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POC
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Vendor Advisories for CVE-2021-1501 (1)
-
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-sipdos-GGwmMerC vendor-advisory x_refsource_CISCO
Same Patch Batch · Cisco · 2021-04-29 · 17 CVEs total
| CVE-2021-1445 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-1504 | 8.6 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-1493 | 8.5 HIGH | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Servi |
| CVE-2021-1476 | 6.7 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Command I |
| CVE-2021-1488 | 6.7 MEDIUM | Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software for Firep |
| CVE-2021-1256 | 6.0 MEDIUM | Cisco Firepower Threat Defense Software Command File Overwrite Vulnerability |
| CVE-2021-1495 | 5.8 MEDIUM | Multiple Cisco Products Snort HTTP Detection Engine File Policy Bypass Vulnerability |
| CVE-2021-1369 | 5.4 MEDIUM | Cisco Firepower Device Manager On-Box Software XML External Entity Vulnerability |
| CVE-2021-1456 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities |
| CVE-2021-1457 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities |
| CVE-2021-1458 | 4.8 MEDIUM | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities |
| CVE-2021-1477 | 4.3 MEDIUM | Cisco Firepower Management Center Software Policy Vulnerability |
| CVE-2021-1402 | Cisco Firepower Threat Defense Software SSL Decryption Policy Denial of Service Vulnerabil | |
| CVE-2021-1448 | Cisco Firepower Threat Defense Software Command Injection Vulnerability | |
| CVE-2021-1455 | Cisco Firepower Management Center Software Cross-Site Scripting Vulnerabilities | |
| CVE-2021-1489 | Cisco Firepower Device Manager Software Filesystem Space Exhaustion Denial of Service Vuln |
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V. Comments for CVE-2021-1501
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